Known windshield wipers have a wiper arm, which is made up of a driven mounting part and a hinge member that is connected to it by a hinged joint and has a wiper rod. A wiper blade is pivoted at the free end of the wiper rod. The wiper blade is guided across the vehicle windshield during the swivel motion of the windshield wiper, an extension spring prestressing the fold-away hinge, so that the wiper blade is pulled toward the vehicle windshield.
The extension spring is accommodated in the u-shaped cross-section profile of the articulated part and is suspended on the articulated part by one end using a cross-pin. By its other end, the extension spring is attached to a spring mount on the mounting part, via a c-shaped clip. In known mounting parts, this spring mount is either preformed or formed by a rivet pin. In one variant, for instance, mounting parts, designed as sheet metal form parts, use a pin as spring mount. During manufacture, this is pressed into holes in the sidewalls of the u-shaped cross-section profile of the mounting part, and then riveted. In contrast to a one-piece mounting part, this requires additional production time for the installation and production of the additional components.
The spring mount is exposed to relatively high forces by the extension spring. In the working position, or fold-away position, these forces also come to bear from different directions, with a 90° difference, for example, resulting in a relative movement between the extension spring or the c-shaped clip and their mountings. To achieve sufficiently high strength, the mounting pin at the mounting part is usually made from a different material than the sheet metal bent component. However, when joining different materials, the danger of contact corrosion exists in the interconnecting region.
In addition to a part of the fold-away hinge and a spring mount, the mounting part also has a mounting region on the opposite end by which the wiper arm is rigidly, but detachably connected to a wiper shaft. The mounting region is designed as a shaft-hub-connection and is formed by a receiving opening having an inner cone, into which the free end of the wiper shaft, which is provided with an approriate outer cone, projects. The two parts are braced by a screw nut. There are also known variants in which the conical interconnecting region is located between a collar of the screw nut and the receiving opening of the mounting part. The form of the receiving opening is created in different ways. If the mounting part is made of a die cast metal or plastic, the receiving opening is usually formed during the die-casting or injection molding, whereas it is produced in several drawing steps if sheet metal bent components are involved.